As efforts increase to decarbonise industry, it’s becoming clear just which aspects necessitate further scrutiny. As the second most consumed substance on the planet, concrete contains a large percentage of cement, the production of which contributes to 7% of global man-made carbon dioxide (CO2) emissions.
The reason cement production contributes so heavily to harmful CO2 emissions is partially due to its energy-intensive nature, but it’s also related to the calcination process - which occurs during production - releasing gaseous CO2.
According to a report by market research and business intelligence experts IDTechEx, carbon capture, utilisation and storage (CCUS) could be a viable method to allow for the production low and even negative carbon concrete.
By making use of CCUS technologies, CO2 produced during calcination and captured at point-source could be stored or used, allowing for the potential mitigation of between 1.5 and 6.3 gigatonnes of CO2 equivalents by 2050, according to the UN.
The key factor for CCUS currently is its limitations; efforts to scale up the technologies and improve the infrastructure surrounding the CO2 marketplace as well as distribution will have to be made.
A possible utilisation method has been proposed by Montreal-based company Carbicrete, which uses captured CO2 to accelerate the curing process of concrete, while strengthening and sequestering the gas.
By using industrial waste as raw material, Carbicrete can produce carbon negative precast concrete blocks, resulting in the company’s claim of 5% for its carbon footprint reduction.
Another tested method is to integrate CO2 into industrial waste powder by-products such as fly ash. Canadian company Carbon Upcycling Technologies claim this technique has reduced its carbon footprint by up to 25%.
As more concrete manufacturing companies are compelled to come up with ever more innovative methods of storing or utilising carbon emissions, further investment will have to be made into the industry by carbon capture companies and solution providers.
The full report on CCUS conducted by IdTechEx can be found here.